From f7a60f6c71f1f4e61ca8d84659df1a556c8919d5 Mon Sep 17 00:00:00 2001
From: Ldoppea <yannick.chiron@gmail.com>
Date: Tue, 26 Nov 2024 17:48:05 +0100
Subject: [PATCH] feat: Debounce PouchDB replication

In #1209 we added CozyPouchLink to CozyClient's instance

By default CozyPouchLink starts replicating all its database directly
after being initialized

This is problematic as this happens during the App's startup and so it
will unnecessary slow the startup process

This is unnecessary because on startup, either the app is offline and
so replication cannot be done, either the app is online and so it will
use the cozy-stack. So replication can be delayed

We want to defer the replication to a short delay after the startup
(for now 30s)
---
 .../authentication/services/AuthService.ts    | 22 +++++++++++++++++++
 src/pouchdb/getLinks.ts                       |  8 ++++++-
 2 files changed, 29 insertions(+), 1 deletion(-)

diff --git a/src/app/domain/authentication/services/AuthService.ts b/src/app/domain/authentication/services/AuthService.ts
index 10c38fc78..58cd35ba1 100644
--- a/src/app/domain/authentication/services/AuthService.ts
+++ b/src/app/domain/authentication/services/AuthService.ts
@@ -2,6 +2,7 @@ import { Linking } from 'react-native'
 
 import type CozyClient from 'cozy-client'
 import Minilog from 'cozy-minilog'
+import PouchLink from 'cozy-pouch-link'
 
 import { asyncLogoutNoClient } from '/app/domain/authentication/utils/asyncLogoutNoClient'
 
@@ -28,8 +29,29 @@ export const handleSupportEmail = (): void => {
   }
 }
 
+const handleLogin = (): void => {
+  try {
+    authLogger.info('Debounce replication')
+    if (clientInstance === null) throw new Error('No client instance set')
+
+    const pouchLink = getPouchLink(clientInstance)
+    pouchLink?.startReplicationWithDebounce()
+  } catch (error) {
+    authLogger.error('Error while handling login', error)
+  }
+}
+
 export const startListening = (client: CozyClient): void => {
   authLogger.info('Start listening to cozy-client events')
   clientInstance = client
   clientInstance.on('revoked', handleTokenError)
+  clientInstance.on('login', handleLogin)
+}
+
+const getPouchLink = (client?: CozyClient): PouchLink | null => {
+  if (!client) {
+    return null
+  }
+  // eslint-disable-next-line @typescript-eslint/no-unsafe-return
+  return client.links.find(link => link instanceof PouchLink) || null
 }
diff --git a/src/pouchdb/getLinks.ts b/src/pouchdb/getLinks.ts
index 8b364cff9..4c4aad766 100644
--- a/src/pouchdb/getLinks.ts
+++ b/src/pouchdb/getLinks.ts
@@ -9,6 +9,9 @@ import { default as PouchLink } from 'cozy-pouch-link'
 
 const log = Minilog('🔗 GetLinks')
 
+export const REPLICATION_DEBOUNCE = 30 * 1000 // 30s
+export const REPLICATION_DEBOUNCE_MAX_DELAY = 600 * 1000 // 10min
+
 export const offlineDoctypes = [
   // cozy-home
   'io.cozy.accounts',
@@ -34,7 +37,10 @@ export const offlineDoctypes = [
 export const getLinks = (): CozyLink[] => {
   const pouchLinkOptions = {
     doctypes: offlineDoctypes,
-    initialSync: true,
+    initialSync: false,
+    periodicSync: false,
+    syncDebounceDelayInMs: REPLICATION_DEBOUNCE,
+    syncDebounceMaxDelayInMs: REPLICATION_DEBOUNCE_MAX_DELAY,
     platform: platformReactNative,
     ignoreWarmup: true,
     doctypesReplicationOptions: Object.fromEntries(